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Name: tim
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: Around 1993

When you turn the key in your car, what makes the engine start?

The key turns on a switch that does two things:

1. sends power to the ignition system so the gas will ignite in the cylinders.

2. energizes the starter solenoid which closes another switch (a very high current switch) that makes the starter motor work that makes the engine turn slowly that causes a fuel-air mixture to enter the cylinders so the ignition system can ignite it. Once a few cylinders have fired, the engine usually runs without the help of the starter motor.

Piece of cake!

jade hawk

When you turn the key, a starter motor turns the engine over until the fuel begins to combust, and the engine runs itself. In the "old" days people started cars by cranking a handle in front of the engine. This basically the same thing. Now the starter motor runs off the battery, and cranks the engine for you.

wildman jackson

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